Explanation:
Close to the Great Bear
(Ursa Major) and surrounded by the stars
of the
Hunting Dogs
(Canes Venatici), this celestial wonder was
discovered
in 1781 by the
metric
French astronomer
Pierre Mechain.
Later, it was added to the catalog of his friend and colleague
Charles Messier as
M106.
Modern deep telescopic views reveal it to be an
island universe --
a spiral galaxy around 30 thousand light-years across located
only about 21 million light-years beyond the stars of the Milky Way.
Along with a bright central core,
this
colorful composite image highlights
youthful blue star clusters and reddish stellar nurseries
tracing the galaxy's spiral arms.
It also shows remarkable reddish
jets of
glowing hydrogen gas.
In addition to small companion galaxy NGC 4248 near the picture's right edge,
background galaxies can be found scattered
throughout the frame.
M106 (aka NGC 4258) is a nearby example of the
Seyfert class of active galaxies,
seen across
the spectrum from radio to x-rays.
Active galaxies are believed to be powered
by matter falling into a massive
central black hole.